To be honest I don't think it would matter if they recast him, with all that make-up on it would be less obvious anyway. And I have always thought Red Skull is more interesting in the present rather than the past in the comics so I would like to see him back however I would also like to see other Cap villains like Zemo get their chance in the spotlight so I don't know if they should bring him back or not. It definitely feels like they had plans to bring him back given the nature of his 'death' in the First Avenger. As for re-casting, I think Kevin Bacon would be awesome in that role, but I don't know if he would do it because of First Class.